In vehicles, it is necessary to supply and control power to various electric components. In order to collectively supply and control power to various electric components in this way, boxes such as a junction box, a joint box, and a battery box are used. Such a box is configured by integrating components such as fuses and relays, and circuit boards.
In recent years, board blocks which are installed in one box or separately equipped with a function of a box are often used. Such a board block performs substantially the same function as that of one box.
A plurality of printed circuit boards are used in the board block, and the printed circuit boards are disposed generally parallel to each other. In order to dispose the printed circuit boards in parallel, the printed circuit boards should be electrically connected by wires or jumper pins. Further, a structure for fixing the printed circuit boards should be provided separately. Thus, the board block according to the related art is relatively large and has a number of components.
The overall size of the board block can be reduced by extending a terminal for coupling components inserted from the outside of the housing in parallel to surfaces of the printed circuit boards while disposing the printed circuit boards in parallel. Thus, the terminal installed in the printed circuit board to be used for the coupling of components should be bent at the right angle unlike a general one. Since the terminal is bent at the right angle, it has a shape different from that of an existing terminal and should be manufactured separately.
Further, since connection unit for electrical connections of printed circuit boards to the outside cannot but be situated at the same location on a lower surface of the housing in the conventional board block, high current circuit patterns should be formed relatively long in the printed circuit boards. Accordingly, significant amounts of heat are generated in the relatively long high current circuit patterns, and the overall size of the board block increases due to the long printed circuit boards.
Furthermore, if many components are installed around the printed circuit blocks in the board block, it is relatively difficult to dissipate heat generated in the printed circuit boards.
In addition, when a separately manufactured board block is mounted to a box, it is important to firmly fix the board block to the box while the board block is not moved with respect to the box. If the board block is moved with respect to the box, operational reliability of the board block deteriorates.